Field-driven helix unwinding in antiferroelectric liquid crystal cells - art. no. 050701

The interaction between the antiferroelectric helix and an electric field a pplied perpendicular to its axis is investigated, both experimentally and t heoretically. A two-stage switching process is observed: (i) in the pretran sitional regime the helix distorts and then unwinds to form a nonhelical an tiferroelectric state, with the plane of the molecules parallel to the appl ied field; (ii) at higher fields switching to the ferroelectric state occur s. The mechanism for unwinding is the interaction of the applied field with a polarization that is induced by a change to the anticlinic ordering.